While major improvements have been made in the collection of epidemiologic data, special populations such as minorities and the medically underserved have been excluded. No accurate epidemiologic information exists on the cancer2 incidence, diagnosis, and treatment of these populations. We propose to explore the stage of diagnosis, treatment, and survival of patients diagnosed with cancer and insured by Medicaid compared to similar patients who are not insured by Medicaid. To conduct this research, we will link the Detroit Metropolitan Surveillance, Epidemiology, and End-Results (SEER) data base with the Michigan Department of Community Health (MDCH) Medicaid claim files. Our specific research aims are: To compare the stage of diagnosis, treatment patterns, and survival of Medicaid recipients to a matched control group of individuals who are not insured by Medicaid and To estimate the cost (using charges as a proxy) of providing cancer care to Medicaid recipients. SEER-Medicaid data offer an opportunity to examine patterns of care during the period of initial cancer diagnosis, as well as long-term follow-up. In addition, we will examine the use of health services and patterns of care for specific cancers by stage at diagnosis. Future projects using the data can include the prevention of disease or disability, the restoration or maintenance of health, and interventions for more effective health care.